On many occasions I have heard people discussing the question "Is artificial intelligence possible at all?".
Now I do not think that this question really deserves much attention. The answer is a clear yes. Unfortunately there is a common perception that the question is relevant and even a significant group of people who take the viewpoint that Artificial intelligence is not possible (It is only for this reason that I address it at all). Generally the reasons given are theological in nature or based on theologically motivated metaphysics. Here is an example of this (in the form of a blog post). I read this and responded but I thought that I should copy my comment (with suitable modifications) here. So that I have done.
On the possibility of artificial intelligence:
All the available evidence indicates that the universe is Turing computable. If anyone can prove, or even find any evidence at all that there was a part of the universe (such as the human mind) that was not Turing computable that would be a huge revolution in physics more significant than any advance since Newton.
And that’s the problem with any contention that AI is not possible. A scientific demonstration that AI is not possible would amount to such new physics as I just mentioned above. Without a scientific demonstration you would be left arguing that you could have something which passes every test you can devise for intelligence and yet you do not regard as being intelligent (likewise conscious etc.). This has the standard solipsistic problems. So the idea that AI is impossible (rather than just very very difficult) is mere wishful speculation and will remain so until some actual evidence to the contrary is presented.
In summary although there is a common viewpoint that AI is impossible or that the question of its possibility is in doubt this is not the case. Indeed if AI were impossible this would be immensely surprising and would certainly result in a noble prize and a place in history besides Einstein, Darwin and Newton for the person who proved it.
I address how difficult I think such a task is in other postings which can be found under the tag AI. Of course one may think that AI is in priciple possible but not practically possible. I also disagree with this viewpoint but not as strongly.